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Impacts on Conventional Generators

NREL is working to understand and quantify the impacts of increased penetrations of solar and wind generation on conventional generators.
With increasing penetrations of wind and solar generation, conventional fossil-fired power plants may be required to adjust their output level and start up or shut down more frequently to accommodate the variability and uncertainty of these technologies. These operational changes can negatively impact plant efficiency and emissions.

NREL's analyses of impacts of renewable electricity generation on conventional generators show that, although the emissions impacts of generator cycling and part-loading can be significant (e.g., combined-cycle generators), these impacts are modest compared to the overall benefits of replacing fossil-fuel generation with variable renewable generation.

Featured Study

A chart showing the actual verses predicted pounds of nitric oxide emissions per year and shows a large spike in the actual over predicted for the 1764-hour marker.

The Western Wind and Solar Integration Study - Phase 2 investigated the cost and emissions associated with increased cycling and ramping of conventional fossil-fueled generation due to higher levels of solar and wind generation. Key findings include that part-load emissions impacts increase the NOx benefits of wind by approximately 8%, while startups and ramping emission impacts reduce the NOx benefits of wind by approximately 4% (based on re-analysis of the Western Wind and Solar Integration Study generation profiles).

To find out more about this study, see Impacts of Wind and Solar on Fossil-Fueled Generators.



Greg Brinkman | 303-384-7390